Oil recovery tool and system

ABSTRACT

An apparatus for generating acoustic waves in a medium to stimulate oil recovery within an oil reservoir, the apparatus being operable with a single moving part—a central rotor.

This application is a continuation-in-part of co-pending U.S. patentapplication Ser. No. 16/270,020 for an OIL RECOVERY TOOL AND SYSTEMfiled Feb. 7, 2019 by R. Valtierra et al., which claims priority under35 U.S.C. § 119(e) to the following provisional patent applications byApplicant Hydroacoustics, Inc.: U.S. Provisional Application No.62/627,310 for an OIL RECOVERY TOOL by R. Valtierra et al., filed Feb.7, 2018; and U.S. Provisional Application No. 62/659,825 for an OILRECOVERY TOOL by R. Valtierra, filed Apr. 19, 2018; and which alsoclaims priority under 35 U.S.C. § 120 as a continuation-in-part of U.S.patent application Ser. No. 16/263,136 (U.S. Pat. No. 10,704,938) for aFLUID SENSOR AND PUMPJACK CONTROL SYSTEM by R. Valtierra et al., filedJan. 31, 2019, all of the above-identified applications being herebyincorporated by reference in their entirety.

The disclosed systems and methods are directed to generating acousticwaves. A downhole oil recovery tool provides a seismic source to enhanceoil recovery. The systems and methods disclosed herein enhance oilrecovery by means of vibratory stimulation, for example, to diminishcapillary forces and encourage the rate of migration and coalescence ofretained oil within the porous media of an oil reservoir.

BACKGROUND AND SUMMARY

After an oil well has been in operation for a time, its productivityoften diminishes to a point at which the operation of the well ismarginal or economically unfeasible. It is frequently the case, however,that substantial quantities of crude oil remain in the ground in theregions of these unproductive wells but cannot be liberated byconventional techniques. Often methods for efficiently increasing theproductivity of a well are considered, provided they can be performedeconomically. Often a borehole can serve as an injection or monitor welland may allow for the insertion of a down hole seismic pressure wavegenerator.

Many methods have been discovered for improving the oil recoveryefficiency, including those disclosed in U.S. Pat. No. 8,113,278 toDeLaCroix et al., for a SYSTEM AND METHOD FOR ENHANCED OIL RECOVERYUSING AN IN-SITU SEISMIC ENERGY GENERATOR (Feb. 14, 2012), which ishereby incorporated by reference in its entirety. Nonetheless, largevolumes of hydrocarbons remain in oil rich formations after secondary,or even tertiary recovery methods have been employed. It is believedthat a major factor causing the retention of the hydrocarbons in suchformations is an inability to direct sufficient pressure forces on thehydrocarbon droplets residing in the pore spaces of the formations.Conventional oil recovery is typically accomplished in a two tierprocess, the primary or initial method is reliant on the natural flow orpumping of the oil within the well bore until depletion. Once the freeflowing oil has been removed a secondary method is required. Generallyan immiscible fluid such as water is forced into an injection boreholeto flush the oil contained within the strata into a production well. Inthe past it has not been cost effective to employ tertiary or enhancedoil recovery (also referred to as EOR) methods, even though up toseventy percent of the total volume of oil may still remain in anabandoned oil well after conventional oil recovery techniques are used.

Another technique that has been employed to increase the recovery of oilemploys the introduction of low frequency vibration energy. Lowfrequency vibration from surface or downhole sources has been used toinfluence liquid hydrocarbon recoveries from subterranean reservoirs.This type of vibration, at source-frequencies generally less than 1 KHz,has been referred to in the literature as sonic, acoustic, seismic,p-wave, or elastic-wave well stimulation. For example, stimulation bylow frequency vibration has been effectively utilized to improve oilproduction from water flooded reservoirs. Examples from the literaturealso suggest that low frequency stimulation can accelerate or improveultimate oil recovery. Explanations for why low frequency stimulationmakes a difference vary, however, it is believed that the introductionof vibrational energy causes the coalescence of oil droplets andre-establishment of a continuous oil phase due to the dislodging of oildroplets from the formation so they can re-combine and coalesce.Additionally it is believed that the sound waves reduce capillary forcesby altering surface and interfacial tensions, and thereby free thedroplets and/or enable them to coalesce. For example, U.S. Pat. No.5,184,678 to Pechkov et al. issued Feb. 9, 1993 discloses a method andapparatus for stimulating fluid production in a producing well utilizingan acoustic energy transducer disposed in the well bore within aproducing zone. However, Pechkov only teaches that ultrasonicirradiating removes fines and decreases the well fluid viscosity in thevicinity of the perforations by agitation, thereby increasing fluidproduction from an active well.

Ultrasonic waves can improve and/or accelerate oil production fromporous media. The problem with ultrasonic waves is that in general, thedepth of penetration or the distance that ultrasonic waves can move intoa reservoir from a source is limited to no more than a few feet, whereaslow frequency or acoustic waves can generally travel hundreds tothousands of feet through porous rock. While sonic stimulation methodsand apparatus to improve liquid hydrocarbon flow have achieved somesuccess in stimulating or enhancing the production of liquidhydrocarbons from subterranean formations, the acoustic energytransducers used to date have generally lacked sufficient acoustic powerto provide a significant pulsed wave. Thus, there remains a continuingneed for improved methods and apparatus that utilize sonic energy tostimulate or enhance the production of liquid hydrocarbons fromsubterranean formations. Acoustic energy is emitted from the acousticenergy transducer in the form of pressure waves that pass through theliquid hydrocarbons in the formation so that the mobility of the liquidhydrocarbon is improved and flows more freely to the well bore. By wayof definition an elastic-wave is a specific type of wave that propagateswithin elastic or visco-elastic materials. The elasticity of thematerial facilitates propagation of the wave, and when such waves occurwithin the earth they are generally referred to as seismic waves.

The value of a barrel of oil and the demand for oil has created agreater interest in tertiary enhanced oil recovery methods to furtheroil availability through the revitalization of older wells, evenincluding those that have been abandoned due to a high ratio of watercompared to the volume of total oil produced, or commonly called thewater cut. The primary intent of enhanced oil recovery is to provide ameans to initiate the flow of previously entrapped oil by effectivelyincreasing the relative permeability of the oil embedded formation andreducing the viscosity and surface tension of the oil. Numerous enhancedoil recovery technologies are currently practiced in the field includingthermodynamics, chemistry and mechanics. Several of these methods havebeen found to be commercially viable with varying degrees of success andlimitations. Heating the oil with steam has proven be an effective meansto reduce the viscosity, provided there is ready access to steam energy,and accounts for over half of the oil currently recovered. The use ofchemical surfactants and solvents, such as CO₂, to reduce the surfacetension and viscosity, while effective, are not widely used due to cost,contamination and environmental concerns. However, seismic stimulationlacks any of the aforementioned limitations and continues to be exploredas a viable enhanced oil recovery technique.

The low-frequency vibration of reservoir rock formations is thought tofacilitate enhanced oil recovery by (i) diminishing capillary forces,(ii) reducing the adhesion between rocks and fluids, and (iii) causingcoalescence of oil droplets and enable them to flow within the waterflood. Studies at the Los Alamos National Laboratory conducted by PeterRoberts have indicated that this process can increase oil recovery oversubstantially large areas of a reservoir at a significant lower costthan other enhanced oil recovery stimulation methods.

The systems and methods disclosed herein provide a low-cost tertiarysolution to facilitate the reclamation of oil that had previously beenuneconomical to retrieve. It is, therefore, a general object of thedisclosed embodiments to enable the use of downhole vibratory seismicsources capable of generating elastic-wave vibration stimulation withinan oil field to extract the immobile oil. By employing an apparatus forgenerating acoustic waves, further oil recovery is stimulated within anoil deposit in fluid contact with a borehole into which the acousticwave source can be placed.

In accordance with the disclosed embodiments, disclosed is anelectro-hydraulic seismic pressure wave source configured as an oilrecovery tool. The operation of the disclosed oil recovery tool isfacilitated by reducing the mechanical complexity of the tool while atthe same time improving its overall reliability. The improvementsinclude integration of a motor into the tool, where the motor isspecifically designed to operate in a water saturated environment. Therotor of the motor is directly attached to drive a rotating valve thatis responsible for creating the seismic wave. The valve is designed withat least one and likely multiple ports for releasing the seismic energy.In one embodiment the oil recovery tool may include smaller ports alongits length to implement a tapered hydraulic bearing. With a taperedbearing the valve uses pressurized water as the “bearing” material toreduce friction and may thereby eliminate the need for custom fabricatedmechanical bearings. With the coupled rotor and valve, and taperedbearing, the tool is essentially reduced to a single moving (rotating)part. Additionally, the rotor is designed with a hollow shaft that, whenattached to the valve, provides a direct path for pressurized supplywater entering the tool to flow to the valve. This allows for greaterfluid flow and reduction in possible cavitation (bubbles forming in thewater). Additional water passages in and around the motor stator providecooling to the motor during tool operation. Additionally, integration ofthe water-saturated motor allows the tool to be reduced in diameterrelative to prior down-hole tools, thereby allowing it to be employed ina larger range of well bore diameters starting at about 4 inches.

Disclosed in embodiments herein is an oil recovery tool for impartingseismic wave energy within an oil reservoir, in the form of a wave, soas to alter the capillary forces of residual oil comprising: a housing;a source of pressurized fluid; and a, brushless motor, operativelylocated within said housing to receive the pressurized fluid andgenerate the seismic waves.

Further disclosed in embodiments herein is an apparatus for generatingacoustic waves within a medium to stimulate oil recovery within an oilreservoir, comprising: an elongated and generally cylindrical housingsuitable for passing through a borehole; an accumulator; a source ofpressurized fluid; an energy transfer section, wherein the energytransfer section may be inclusive of the pressure transfer valve, andfurther including, a motor; a hollow-shaft rotor having an output port;and a stator having a corresponding output port whereby fluid energy istransferred upon alignment of said rotor and stator ports, wherein themotor is operatively connected to the hollow-shaft rotor and where fluidpasses therethrough to the accumulator; and a pressure transfer valve,wherein the pressurized fluid is stored within said accumulator andsubsequently transferred, thereby releasing seismic wave energy via theports into the fluid surrounding the apparatus.

Also disclosed herein is a method for generating seismic pressure waveenergy within an oil saturated strata, comprising: placing an acousticwave generator in contact with a fluid within the strata; accumulatingfluid pressure energy within the acoustic wave generator; andperiodically releasing and transferring pressure energy with saidgenerator to create wave energy that is transferred by the fluid into aporous medium of the strata, wherein releasing and transferring energyis accomplished by a motor driving a rotary valve generator, said valvegenerator employing a hollow shaft for fluid passage, whereby therelative relationship of output ports on both a rotor and a statorwithin the fluid generator controls the release and transfer of asystematic pressure pulse to create the seismic pressure wave energy.

Further disclosed herein is an oil recovery system for enhancing therecovery of oil within a reservoir, including: a source of pressurizedfluid; a submersible oil recovery tool for imparting seismic wave energywithin the oil reservoir, in the form of a wave, so as to alter thecapillary forces of residual oil therein, comprising, a housing; and abrushless motor, operatively located within said housing to receive thepressurized fluid and generate the seismic waves; and a control systemsuitable for monitoring and controlling the system components includingat least the oil recovery tool and the source of pressurized fluid toproduce seismic waves within the reservoir.

Also disclosed herein is a system for generating acoustic waves within amedium to stimulate oil recovery within an oil reservoir, comprising: asource of pressurized fluid, wherein said source of pressurized fluidincludes a replenishable fluid reservoir and a pressurization system forpressurizing the fluid from said reservoir and passing the pressurizedfluid through a conduit, the conduit terminating at an opposite end atan oil recovery tool, said oil recovery tool including; an elongated andgenerally cylindrical housing suitable for passing through a borehole;an accumulator; an energy transfer section including, a motor, ahollow-shaft rotor having an output port, and a stator having acorresponding output port whereby fluid energy is transferred uponalignment of said rotor and stator ports, wherein the motor isoperatively connected to the hollow-shaft rotor and where fluid passestherethrough to the accumulator; a pressure transfer valve, wherein thepressurized fluid is stored within said accumulator and subsequentlytransferred, thereby releasing seismic wave energy via the ports intothe fluid surrounding the apparatus; and a control system suitable formonitoring and controlling at least the oil recovery tool and the sourceof pressurized fluid to produce seismic waves within the reservoir.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-3 are front, side and top illustrations of an embodiment of theoil recovery tool;

FIGS. 4 and 5 are, respectively, cross-sectional views of FIGS. 1 and 2along lines A-A and B-B;

FIGS. 6 and 7 are, respectively, cross-sectional top views of FIGS. 4and 5 along lines C-C and D-D;

FIG. 8 is a partial cut-away illustration of an embodiment of the oilrecovery tool;

FIGS. 9 and 10 are enlarged cross-sectional illustrations of alternativeembodiments for the motor assembly and port portions of the oil recoverytool;

FIGS. 11-13 are illustrations of various components for an exemplarydrive motor for the oil recovery tool of FIG. 1 , with FIG. 12 depictinga cross-section along lines A-A of FIG. 11 ;

FIGS. 14-17 are illustrations of various embodiments and applicationsfor a venturi-based sensor in accordance with the disclosed system andmethod;

FIGS. 18-19 are, respectively, illustrative examples of a method ofinstalling a venturi sensor, and monitoring and control circuitry forincorporating the sensor into a pumpjack well system;

FIGS. 20-24 are illustrative graphs of exemplary pressure andcapacitance data generated by the disclosed sensor and control system;

FIGS. 25-27 provide schematic illustrations of an exemplary oil recoverysystem and method employing venturi sensors and an oil recovery tool inaccordance with an embodiment of the disclosed oil recovery system; and

FIG. 28 is a schematic illustration of a submersible oil recovery tool,and the components thereof.

The various embodiments described herein are not intended to limit thedisclosure to those embodiments described. On the contrary, the intentis to cover all alternatives, modifications, and equivalents as may beincluded within the spirit and scope of the various embodiments andequivalents set forth. For a general understanding, reference is made tothe drawings. In the drawings, like references have been used throughoutto designate identical or similar elements. It is also noted that thedrawings may not have been drawn to scale and that certain regions mayhave been purposely drawn disproportionately so that the features andaspects could be properly depicted.

DETAILED DESCRIPTION

Early oil recovery tool (ORT) embodiments employed pressurized fluidreleased in pulses as described herein. Such tools required complexmechanical components and internal fluid pathways, bearings with sealsto provide fluid to the tool and to produce suitable seismic energy orwaves. Earlier tools also required a separate pump(s) to gather andpressurize fluid.

Oil Recovery Tool

The oil recovery tool embodiments 110 described herein may be employedfor imparting seismic wave energy (e.g., in the form of a wave) withinan oil reservoir, so as to alter the capillary forces of residual oil.The tool comprises: a housing 112; a source of pressurized fluid 114 andelectrical power. And, as described relative to FIGS. 1-13 , the housingintegrates a water-saturated, brushless motor, operatively locatedwithin the housing to receive the pressurized fluid and turn a rotorrelative to a stator and align respective ports therein to generate theseismic waves.

In accordance with the improved embodiments depicted in FIGS. 1-13 , anelectro-hydraulic seismic pressure wave source is illustrated,configured as an oil recovery tool 110. The operation of the disclosedoil recovery tool 110 is facilitated by reducing the mechanicalcomplexity of the tool while at the same time improving its overallreliability. The improvements in one embodiment include integration of amotor assembly (e.g. water-saturated) 120 into the tool, where the motoris specifically designed to operate in a water-saturated environment.The rotor 122 of the motor is directly attached to drive the rotor of arotating valve assembly 130 that is responsible for creating the seismicwave. The valve assembly, which may also be characterized as theacoustic wave generator, is designed with multiple ports 134 (166) forreleasing the seismic energy, and with the addition of smaller ports 136along its length to implement a tapered hydraulic bearing. The portshave a cross-sectional slot shape, but may also have shapes such ascircles, squared notches, etc. to alter the profile and characteristicsof the generated seismic wave. It will be further contemplated that thevalve assembly or acoustic wave generator portion of the oil recoverytool 110 may employ alternative mechanisms for opening and closing theports 136 in a controlled fashion to generate the acoustic or seismicwaves.

The valve assembly rotor 122 may be supported for rotation relative tothe surrounding stator using any of a number of possible bearingtechniques, including frictionless materials such as Teflon® to supportsurfaces of the rotor. Also contemplated are customized rolling bearingsemploying conventional inner and outer rings supported by balls orrollers and including seals to reduce friction due to bearingcontamination. In another embodiment a tapered bearing valve usespressurized water (from source 114, flowing through the motor assembly120 and the rotor 154) as the “bearing” material to reduce friction andthereby eliminate the need for custom fabricated mechanical bearings andassociated seals. With the coupled rotor and valve assembly, and taperedbearing, the tool is essentially reduced to a single moving (rotating)part—the rotor 154 of the valve assembly, driven by the attached rotor122 of motor 120. Additionally, both rotors are designed with a hollowshaft or core 126 that, when attached to the valve assembly, provides adirect path for pressurized supply water entering the tool 110 to flowthrough the motor to the valve assembly and the accumulator 180. Thisallows for greater fluid flow and reduction in possible cavitation(bubbles forming in the water). Additional water passages in and aroundthe motor stator (e.g., passages 116 in FIGS. 9-10 ) provide cooling tothe motor during tool operation. Additionally, integration of thefluid-saturated or water-saturated motor; allows the tool outer housing112 to be reduced in diameter relative to prior tool designs, therebyallowing the current embodiment to be employed in a range of smallerwell diameters, with bore diameters starting as small as about 4.0inches.

While FIGS. 1-13 illustrate a linear ordering of the motor 120, valve(e.g., rotor and stator), and accumulator 180, it will be appreciatedthat a fluid-saturated motor allows for alternative arrangements of suchcomponents. For example, when the tool 110 is considered in an operativeposition within a borehole or fluid reservoir, the oil recovery systemmay include an accumulator positioned below the rotary valve asdepicted, or the accumulator may be positioned above the rotary valve.Moreover, in one contemplated embodiment, wherein the accumulator ispositioned above the rotary valve, the motor may be positioned below therotary valve.

Turning to FIGS. 1, 4-5 and 8-10 specifically, depicted therein arecross sectional and cut-away illustrations of the oil recovery tool(ORT) 110 embodiments and the assembled mechanical components. Specificcomponents are labeled and include, for example, motor assembly 120,upper bearing surface 150, rotor 154, stator 158, rotor port or orifice162, stator port or orifice 166, lower bearing surface 170, and pressureaccumulator 180. From FIGS. 1-10 one can see how the motor assembly androtating valve are operatively coupled together into a single rotatingpart and how they are compactly integrated into tool 110.

Considering FIGS. 9 and 10 , depicted are enlarged views of the motorassembly 120 in two alternative embodiments of the tool 110. The motorstator 156 and rotor 122 are shown and the rotor rotates within thestator. The interface 128 to valve 130 is depicted along with a customthreaded screw 190, which attaches the motor rotor to the valve. As morefully illustrated in FIGS. 11-13 , the rotor includes a core surroundedby permanent magnets 127. The rotor rotates inside of the stator. In oneembodiment the stator includes the motor windings, which receive powerto control operation of the motor from the surface via wires passingthrough the bulkhead. In the illustrated embodiment of FIGS. 1-8 , toincrease the downhole range (depth) of the tool 110, a motor controller194 may also be incorporated within the tool housing such that theelectrical connections to the surface need only include power andcontrol signals. The motor controller 194 is part of a small printedcircuit board or similar electronics assembly that is suitable toinstallation within housing 112, and the motor assembly 120 is connectedto and powered-by the controller via wires 196.

Referring to FIG. 10 , the alternative design of the motor assemblysection 120 of the tool 110 is illustrated. In the alternative design,certain components are modified or added, some to adapt tool 110 tohigher pressures with an extended downhole depth. The modificationsfurther serve to prevent water ingress into the controller chamber andeliminate erosion of the potting material caused by pressurized liquid.Some of the changes include a stator 158 that is no longer potted inplace. Also, O-rings 152 are larger (e.g., longer and/or thicker) toaccommodate higher operating pressures of up to 4000 psi, and to provideincreased isolation of the motor stator from the casing and surroundingcomponents. The motor assembly 120 may include a longer or extendedtitanium sleeve 144 needed to accommodate the additional isolationO-rings 152 located at the top and bottom of the motor stator chamber.The stator 156 of motor assembly 120 is also biased in an upwardposition by a spacer 146 pressed against the lower end of the stator bya wave spring 148 resting on shoulder 150. The ring-shaped spacer 146further protects the motor potting material from damage by wave spring148, by distributing the spring load and thereby reducing vibration andpulsing being transmitted directly from the spring to the pottingmaterial.

Calling attention to the screw 190, the hollow aspect of the screw canbe seen to illustrate a passage 192 for water to be fed to the valvedirectly through the motor. Depicted in red is a custom bulkheadconnector 198 used to route electrical wiring from the motor out of thetool 110.

Turning next to FIGS. 11-12 , depicted therein are details of the motorassembly 120. There are inner (e.g., titanium) and outer (e.g.,stainless steel) metal “shells” 144, 222 and 224 respectively, placedadjacent the stator 158 along with potting resin 230 to protect themotor against environmental wear, corrosion and stress resulting fromhigh pressure water, water flow induced wear, etc. As previously notedrelative to the embodiment of FIG. 10 , the motor stator 158 may beisolated from the environment by the O-ring seals 152.

In summary, the oil recovery tool 110 is an apparatus for generatingacoustic/seismic waves within a medium to stimulate oil recovery withinan oil reservoir. The oil recovery tool embodiments 110 describedinclude: an elongated and generally cylindrical housing 112 suitable forpassing through a borehole (not shown). The housing may be made from oneor a combination of materials including stainless steel (304, 409 or2507) or plated steel (e.g., electroless nickel, nickel-boron or SeaTEC100). The tool includes an accumulator 180 for accumulating a reservoirof pressurized fluid, for example, from a surface source. In oneembodiment the accumulator 180 includes commercial off the shelfcomponents, such as a rubber bladder that decouples the pulsations fromthe pressure supply source. While various techniques may be employed toprovide an accumulator to collect pressurized fluid for release throughthe ports, in one embodiment of the tool, the pressure is releasedmultiple times (e.g., twice) during each complete rotation)(360° of therotor 122; where the ports are generally closed but opened for about5°-15° of each half-rotation. The effective area of the port or opening(e.g., axial length x rotational length), in conjunction with theaccumulator size and fluid pressure, govern the pressure drop, andassociated acoustic energy release over each discharge cycle. It is alsopossible that a wider or a longer slot 162, 166 (greater area), allother aspects being constant, will reduce the average pressure in theaccumulator. In addition to the port size, the port shapes may becustomized to change the harmonic content and the nature of the acousticpulse created by the tool.

The tool also includes an energy transfer section inclusive of thepressure transfer valve and includes the motor 120, a hollow-shaft rotor154 having an output port, and a stator 158 having a correspondingoutput port whereby accumulated fluid energy is transferred through theoutput ports upon alignment of the rotor and stator ports, and where themotor is operatively connected to the hollow-shaft rotor (and fluidpasses therethrough to the accumulator). A pressure transfer valve isemployed, wherein the pressurized fluid is stored within the accumulatorand subsequently transferred, thereby releasing seismic wave energy tothe surrounding borehole fluid/strata via the ports.

As will be appreciated, a method for generating a pressure wave withinan oil saturated strata using the oil recovery tool 110 may comprise:placing the tool in contact with a fluid within the strata; accumulatingfluid pressure energy (e.g., an acoustic wave) within the tool; andperiodically releasing and transferring pressure energy with the tool tocreate wave energy via releasing the fluid into a porous medium of thestrata, where releasing and transferring energy is accomplished by themotor driving a rotary valve generator—the tool employing a hollow shaftfor fluid passage, whereby the relative relationship of output ports onboth a rotor and a stator within the housing controls the release andtransfer of a systematic pressure pulse or wave.

Output Monitoring

Having described the oil removal tool, attention is turned to a fluidsensing system suitable for sensing the fluid being removed from a well.Referring to FIGS. 14-17 , depicted therein are various views of a fluidsensor 610. In the illustrated example, fluid sensor 610 includes a2-dimensional venturi 620, where the venturi causes pressurized fluid(s)pumped therethrough to take the form of a controlled thickness ofnon-stratified fluid as the fluid flows. The 2-dimensional venturi 620reduces or eliminates stratification of the fluid flowing therethroughas a result of the combination of the 2-dimensional venturi region andthe “necking” down of the incoming cylindrical fluid passage 622 into athin, planar region 624. Venturi 620 also includes a first fluidpressure sensor 630 located on inlet 632 to the venturi to measure apressure for the pumped input fluid. A second fluid pressure sensor 640is located on the outlet side 642 of the venturi 620 to measure apressure of the output fluid. It will be noted that one or both sensors630 and 640 may also be suitable for sensing the temperature of thefluid passing thereby to provide fluid temperature data as well aspressure data.

In one embodiment, venturi 620 may be 3D printed fromstereolithography-compatible resin or similar non-magnetic material. Itis also contemplated that the venturi may be injection-molded ormachined using other well-known techniques. For durability, the venturior other sensor components may be incorporated into a metal pipe (e.g.,FIG. 14 ) and potted using a durable epoxy resin. The pressure sensors630 and 640 are sensors that may be obtained from TE Connectivitycompany, for example Part No. MS5803-05BA. While a fluid sensor 610 madewith polymeric components such as polyvinyl chloride (PVC), etc.) may besuitable for relatively limited (low) pressures in ranges of up to 50psi or even 70 psi, it will be appreciated that the fluid sensor mayalso be designed for use in higher-pressure applications exceeding 70psi. For example, with alternative materials and seals (e.g.,thicker-walled steel or stainless steel components, high-pressuregaskets and seals, etc.), the disclosed sensor may be employed onpressurized wells and the like. In such an embodiment, use of adifferential pressure probe(s) is contemplated to handle the increasedrange of pressures that the venturi sensor may experience.

Another aspect of the 2-dimensional venturi 620 is that it provideslarge planar regions 624 on either side thereof to which a capacitivesensor 660 is attached adjacent the venturi. More specifically, thecapacitive sensor includes a pair of parallel conductive metal plates664 (e.g., made of copper, brass, etc., and of approximately 5 sq. in.and 0.01 in. thickness) located on each side of the 2-dimensionalventuri. In one embodiment copper plates are employed as it is easy tocut them to the appropriate size, and a conventional solder may beemployed to attach electrical wire leads to the sensor plates 664. Acapacitance measured between the plates is output as a dielectricstrength of the fluid flowing through the venturi, where the capacitanceallows for the characterization of the fluid—and in particular theability to distinguish between the presence of water versus oil flowingthrough the sensor by the relative difference in dielectric strength.

Using the pressure differential measures as a difference between theoutputs of the first pressure sensor 630 and the second pressure sensor640, it is possible to determine a fluid flow rate as a result of boththe size of the 2-dimensional venturi and/or calibration of the venturiitself. Accordingly, the fluid sensor 610 allows the device to determinea fluid flow rate as a function of the input fluid pressure from sensor630 and output fluid pressure from sensor 640.

In one embodiment, such as that depicted in FIGS. 14 and 17 , the sensor610 is contained within a housing 670, which is outfitted with standardthreaded nipples 672 or similar couplings 674 on either end thereof toprovide the sensor as a complete unit suitable for being plumbed orretrofitted in-line into a pumpjack well piping system such as depictedin FIG. 18 . Moreover, as a result of the depicted design, the venturi620 and sensor 610 are completely self-draining after the pumpjack isshut down, thereby avoiding fluid (e.g., water) collection and potentialdamage to the sensor due to freezing conditions, etc. As previouslysuggested, the use of a 2-dimensional venturi design, in combinationwith the necking-down of the cylindrical pipe cross-section to a linearslit at the entrance to the venturi (see e.g., end view of planar region624 in FIG. 16 ), avoids fluid stratification. Another characteristic ofthe disclosed sensor embodiment is the maximization of the capacitiveplate surface area while maintaining a compact sensor assembly.

Having described the details of the fluid sensor 610, attention is alsoturned to FIGS. 18-19 , which are provided to illustrate an embodimentof a pumpjack monitoring and control system, as well as the datacollected from the system and processed. More specifically, a pumpjackmonitoring and control system 610, such as depicted in FIGS. 18-19 mayconsist of or include an in-line fluid sensor 610 in a housing 670,where the sensor is operatively coupled or plumbed, for example viacouplings 674, to receive the fluid output of a pumpjack 720 connectedto a wellhead. In the depicted configuration, sensor 610 is used togenerate and output pressure and capacitance signals in response to thefluid output, the output signals being transmitted via a wire or cable726 to control and logging circuitry within the venturi electricalcontroller 740. The fluid sensor, as described above, includes a firstfluid pressure sensor at the inlet to the venturi, a second fluidpressure sensor at an outlet of the venturi, and a capacitive sensoralong the 2-dimensional venturi, where the capacitive sensor includes apair of parallel conductive metal plates on each side of the2-dimensional venturi.

The system 710 also consists of or comprises a controller 740, operatinga micro-processor or similar microcontroller 754 in accordance with aset of pre-programmed instructions. The controller 740 includes aprinted circuit board 750, with an I/O port that receives output fromthe fluid sensor 710 via the cable 726 connected at port 728, andprocesses the output signals. In addition to data retrieval theconnections to other devices may enable the exchange of informationother than sensor data, including programmatic upgrades and the like. Inone operating mode, the controller 740 (e.g., a single board computeravailable from Texas Instruments company) may operate simply as a datacollection device, receiving and storing the sensor output signals inmemory (not shown), including converting the signals from an analogoutput into a digital value for storage. Also included is a pin-typeplug or port (e.g., 4-pin) 764, providing wired connectivity for to thepumpjack (e.g., power and motor control signals). Wireless connectivityis also provided via a localized Bluetooth or Wi-Fi connection betweenthe controller and a portable computing device (not shown), and alsocontemplated is a mobile telephony or satellite link that may beintegrated into controller 240 to facilitate remote data exchange.Furthermore, a digital display 260 may be provided with controller 240,to provide status or operational information as well as real-time outputof pressure or other data. Although not shown it will be appreciatedthat the system 210 further includes a power source, which may includeone or more batteries for primary or backup power.

Referring briefly to FIGS. 18-19 , in one embodiment the venturi sensormay include an embedded digital controller with which it communicateswith controller 740 via a digital UART signal (e.g., RS232). The venturisensor system sends pre-digitized values for pressure, temperature, andcapacitance to the controller. The electronics assembly is placed intoan enclosure such as a pipe, and is then filled (potted) with epoxy. Acenter electronics board includes the microcontroller, whichcommunicates with the pressure sensors 630, 640, measures capacitance,stores and transmits a digital stream of sensor data to the pumpjackcontroller 740. Two outer boards, 830, 840 may be used for mounting thepressure sensors. Alternatively, as illustrated in FIG. 15 , thepressure sensors 630 and 640 are directly coupled to the electronicsboard 618 via a wired harness or bus. For example, employed in oneembodiment is a digital bus 650 (ribbon cable) that the microcontrolleruses to communicate with the pressure sensors. The embedded digitalcontroller is primarily employed to convert the analog sensor signals todigital signals to mitigate noise that is usually associated with atransmitted analog signal (especially when measuring capacitance).Lastly, the ability to sense temperature of the fluid flowing throughthe sensor allows for a more accurate characterization of the fluidpressures.

In another embodiment, the controller, or another computer processor(not shown) to which the controller 740 is linked (wired (e.g., port728) or wirelessly), may use the output signals to monitor the pumpjackoutput and, based upon such signals, analyze and report the performanceof the pumpjack as, for example, depicted in FIGS. 20-24 . Moreover, thecontroller or other computer may process the output signals to totalizethe amount of oil and/or water pumped from the wellhead over a period oftime based upon the differential pressure data between the first andsecond pressure sensors. As noted above, the pumpjack monitoring andcontrol system may include a wireless transceiver for communicating datawith another computerized device.

The pumpjack monitoring and control system 710 may also process the datafrom the sensor 610 and modify the operation of the pumpjack to optimizeextraction of oil from the wellhead. For example, the system may beemployed to determine, based upon real-time output signals from sensor610, whether oil, water or gas are being pumped and passed through thesensor. And, based upon such a determination the pumpjack operation maybe continued, stopped or otherwise adjusted accordingly. As an example,upon detecting the pumping of oil, the operation of the pumpjack iscontinued whereas upon the detection of water or gas the operation ofthe pumpjack may be stopped or modified. In one embodiment, the systemdetermines or distinguishes the type of fluid in the sensor based uponthe pressure and capacitance signals being generated by the sensor. Forexample, the system may employ one or more of the following rules:

-   -   a) oil=high stroke pressure in combination with low capacitance;    -   b) water=high stroke pressure in combination with high        capacitance; and/or    -   c) gas=low stroke pressure in combination with low/oscillating        capacitance.

As illustrated in FIG. 20 , for example, each stroke of the pumpjackcreates a pressure “spike” in the differential pressure (610) betweenthe input and output sensors (630 and 640, respectively). And, when thefluid transitions from oil to water, at approximately 80 seconds in thechart, the change in the pressure profile (slight decrease in peakpressure due to water) is concurrent with a similar increase in themeasured capacitance (also consistent with water instead of oil beingpresent in the 2D-venturi).

As illustrated in FIG. 21 , the observed differential (or absolute)pressure initially increases (e.g., pressure buildup region 410) above anominal level when the pumpjack starts and begins to pump fluid throughthe sensor. And when the accumulated fluid in the well has been pumpedoff (e.g., well pumped-off region 420), the pressure decreases back tonear the nominal pressure level as shown in FIG. 22 .

FIG. 23 is provided to illustrate how the controller records atime-series for the entire pumping cycle. Collection of the data allowsfor post processing to calculate the volume/water cut data, which canthen be employed to facilitate greater accuracy of measurements. Anytime fluid is pumped from a well it is expected that the fluid may be acombination of oil and water. Typically, “water cut” is the ratio orpercentage of oil/water that was pumped. For example, for the welltested (see e.g., FIG. 23 ), upwards of 95-percent of the fluid beingpumped may be water. Thus, the water cut would be characterized as95-percent. The availability and analysis of data collected acrossentire pumping cycles facilitates the use of “learning”, includingcomparison against prior data and pattern detection within the data, tofacilitate adjustment of control parameters based upon past performancedata for the pumpjack/well. And, as suggested above and in FIG. 24 , thedata from the sensor might also be used to allow the system to detectthe presence of gas or foam within the fluid pumped from the well andpassed through the sensor. For example, region 430 of the graph shows acombination of low pressure plus low/oscillating capacitance that mayindicate the presence of foaming or gas.

Oil Recovery System

Having described both an oil-recovery tool and an output monitoringsystem suitable for use in an oil field 1110, attention is now turned toFIGS. 25-27 . Depicted in FIG. 25 are a plurality of wells 1120, eachhaving associated therewith a pump or other mechanism for extracting andcollecting liquids (including oil) from the well. At least one of thewells also has a ground-level monitoring system 1130 such as depicted inFIGS. 14-19 operatively associated with the well, whereby the monitoringsystem is capable of generating data indicative of the amount of oilbeing produced from the well 1120. The ground-level monitoring systemmay also be capable of storing and/or transmitting data indicative ofthe oil volumes and related information to remote station 1150 via oneor more communications channels (wired, wireless (e.g., satellite,microwave, WiFi, etc.)). The remote station 1150 includes both acomputer system and data storage capability, wherein the computer systemis capable of parsing and analyzing the collected data from one or moreof the wells in field 1110 to assess performance of the field andparticular wells over time and in response to various processes andtreatments. One of such treatments may include the use of seismic oracoustic energy to stimulate the oil field in a manner suitable toincrease the output of the wells and thereby improve the performance ofthe oil field in general.

Referring also to FIG. 26 , depicted therein is an oil recovery system1210, where an oil recovery tool 110 is employed within a borehole 1240(e.g., at or below the fluid level), and is controlled by the system1250 as depicted in FIG. 26 . The oil recovery system 1210 for enhancingthe recovery of oil within a reservoir, includes a source of pressurizedfluid 1260, a submersible oil recovery tool 110 for imparting seismicwave energy within the oil reservoir 1110, in the form of a wave, so asto alter the capillary forces of residual oil therein, and a controlsystem 1250 suitable for monitoring and controlling the systemcomponents including at least the oil recovery tool and the source ofpressurized fluid to produce or generate seismic/acoustic wave energywithin the reservoir. The oil recovery tool 110 includes a housing and abrushless motor, operatively located within the housing, as described indetail above, to receive the pressurized fluid and, in response toelectrical power, generate the seismic/acoustic energy waves by releaseof pressurized fluid through aligned ports of the rotor and stator.

The source of pressurized fluid includes a replenishable fluid (e.g., aliquid such as water) reservoir 1264, a pressurization system forpressurizing the fluid from the reservoir and passing the pressurizedfluid through a conduit 1268 to the oil recovery tool 110. In oneembodiment the conduit 1268 is formed of multiple sections of tubingattached to the oil recovery tool 110 and assembled end-to-end as thetool is lowered into borehole 1240. In an alternative embodiment theconduit may include a flexible material suitable to be repeatedlylowered and raised in a borehole, possibly wound and unwound as neededfrom an optional reel 1300 (e.g., high-pressure hose or coiled tubing).The pressurization system includes a pump 1272 driven by motor 1270, incombination with a filter 1274, along with at least one sensor 1276(e.g., fluid supply pressure (P) from pump, fluid flow rate (F) to oilrecovery tool, pump motor current (A), fluid back pressure (P_(B)) atfilter, etc.)) generating a signal and sending said signal to saidcontrol system.

It will be appreciated that in a simplified embodiment, generation ofseismic waves via the oil recovery tool 110 involves an operator placingthe tool in a borehole at a desired depth and providing, via the conduit1268, a pressurized fluid (e.g., liquid) to operate the tool. In such anembodiment, any of a number of methods of controlling the rate andpressure of the fluid may be implemented on the surface. As illustratedin FIG. 26 , one example of an embodiment of control system 1250 furtherincludes a programmable logic controller 1280, a single-board computer1282, and at least one external communication transceiver (Tx/Rx 1284)(e.g., WiFi, Bluetooth, Ethernet, satellite modem (Irridium)). Theprogrammable logic controller uses a multi-core microcontroller andprovides low-level controls by interfacing with and providing controlsignals and/or power (e.g., control/contactor for motors) to both thepump motor 1270 and the brushless motor in the oil recovery tool 110,and where the single-board computer is operatively connected to exchangecommands and data with the programmable logic controller to effectuatevarious operations of the oil recovery system 1210 to consistentlyproduce the seismic wave energy. In one embodiment the single-boardcomputer 1282 employs a Linux-based operating system and storedprogrammatic instructions are employed for a plurality of functions. Aswill be appreciated, the oil recovery system, through the externalcommunication transceiver, and in conjunction with the single-boardcomputer, enables both autonomous and remote control of the oil recoverysystem. Such remote control may be effectuated via remote station 1150as depicted in FIG. 25 , whereby the operation, control and monitoringof system 1210 can be accomplished remotely, or at a centralized controlconsole. Among other data, the oil recovery system permits the remotemonitoring of operating parameters of the system (e.g., sensor data,control status, system faults, etc.) and facilitates the remotegeneration of commands to adjust certain parameters (e.g., the recoverytool motor speed (i.e., frequency). The ability to be able to adjust theoperation of the oil recovery tool has the potential to avoid time andcost to conduct pre-studies of the oil field to pre-determine desirableoperating characteristics. Indeed, the oil recovery tool can be deployedwithin a field and, with the previously-described monitoring equipment,the operations can be monitored and adjusted so as to optimize theperformance and “tune” it for an oil field.

To provide for reliable performance, various components of the systemmay be optimized. For example conduit 1268, used to provide thepressurized fluid to oil recovery tool 110 is capable of handling afluid pressure of up to at least 1500 psi, although normal operatingpressures are typically in the range of about 250 to about 350 psig. Insome deeper well uses, it is contemplated that the conduit 1268 and oilrecovery tool need to be able to handle pressurized fluid (e.g., liquid)at pressures up to at least 7500 psi. Furthermore, in one embodiment,the conduit may be formed of a flexible (windable) material suitable forrepeatedly being wound and unwound upon a reel to raise and lower thetool within the borehole, where the conduit further serves as anumbilical connection attached to and capable of lowering and raising theoil recovery tool relative to a borehole 1240 to adjust its depth.Alternatively, instead of being flexible, the conduit may be formed of agenerally rigid material (e.g., steel tubing with piping assembledend-to-end), where the steel tubing with piping serve as a connectionto, and capable of lowering and raising, the oil recovery tool relativeto the borehole.

In summary, the system depicted in FIGS. 25-25 is capable of generatingacoustic waves within a fluid medium to stimulate oil recovery within anoil reservoir. The system includes a source of pressurized fluid 1260,wherein the source includes a replenishable fluid (e.g., a liquid suchas water) reservoir 1264 and a pressurization system (motor 1270, pump1272, filter 1274, and sensors 1276) for pressurizing the fluid from thereservoir and passing the pressurized fluid through the conduit, theconduit 1268 terminating at an opposite end at the oil recovery tool110. And, as described above, the oil recovery tool is generallyretained with an elongated and generally cylindrical housing suitablefor passing through a borehole. The tool itself includes an accumulator;an energy transfer section (may be inclusive of the pressure transfervalve), a motor, a valve such as a hollow-shaft rotor having an outputport, and a stator having a corresponding output port whereby fluidenergy is transferred upon alignment of the rotor and stator ports, andwhere the motor is operatively connected to the hollow-shaft rotor sothat fluid passes therethrough to the accumulator. The motor, which maybe frameless, is powered from the surface via the programmable logiccontroller via current-carrying wires associated with a conduit. As usedherein the term “frameless” is intended to characterize a motorconfiguration that does not require a separate housing or frame toencompass the motor components, but where an associated structure (e.g.,the outer housing of the oil recovery tool) serves the purpose ofretaining the motor components in an operational relationship.

As described the oil recovery tool, and the motor therein, operate as apressure transfer valve, wherein the pressurized fluid is stored withinthe accumulator and subsequently transferred through the ports into thesurrounding fluid, thereby releasing seismic wave energy into the fluidsurrounding the tool. The control system 1250 is suitable for monitoringand controlling at least the oil recovery tool and the source ofpressurized fluid to produce the seismic waves within the reservoir. Theoil recovery system 1210 produces a seismic wave at a frequency betweenabout 10-100 Hz, and more preferably between 15-50 Hz.

As will be appreciated, the programmable logic controller 1280 and thesingle-board computer 1282 each include respective programmaticinstructions for their operation, and the single-board computer includesprogrammatic instructions suitable for interfacing with and controllingcertain operations of the programmable logic controller. As previouslydescribed relative to FIG. 27 , the system may also include remotecomputer or computing station 1150, the remote computer including astorage medium suitable to storing programmatic instructions where theinstructions facilitate a remote connection to the single-board computer1282 via a communications channel selected from the group consisting ofWiFi, Bluetooth®, Ethernet, and satellite modem. Using the remotecomputer, it is possible to both monitor the production of wells using aground-level monitoring system 1130, as well as control and adjust theseismic output of the oil recovery tool 110, to optimize the output ofoil field 1110.

The various components described relative to system 1210, depicted inFIGS. 25-27 , need to reliably operate even though subject to powerfluctuations and outages. To assure that the system 1210 is capable orreturning to operation after a shutdown, one of the programmable logiccontroller and/or the single-board computer include non-volatile memory(NVM) suitable for storing data generated by the system. In oneembodiment, the stored data includes an indication of whether the systemis performing a restart after one of at least two events (e.g., aplanned power-down or a blackout power-down).

With respect to FIG. 27 , at the top of the figure a ground-levelmonitoring system 1130 is shown producing output from a sensor such as aventuri-type sensor, where the data may be processed (e.g., classified)by processor 1252 so as to characterize an amount or rate of oilproduced from the associated well. The oil production data is thenpassed or further processed (e.g., remote station 1150) where the oilproduction data is compared and contrasted, and an algorithm or otherartificial intelligence operations may be employed to determine whetheradjustments should be made on the operating parameters of oil recoverysystem 1210, whereby the remote station may relay new parameter settings(e.g., frequency, pressure, depth) back to the recovery system tooptimize performance of the oilfield. It will be further appreciatedthat the remote station may process input from a plurality of wellmonitoring systems, and that the oil production data from suchmonitoring systems may be concurrently used to optimize production of aseries of wells in a field, even though one or more wells may notthemselves be optimized. In summary, a classifier (e.g., processor 1252)analyzes the raw data output from the venturi sensors in monitoringsystem 1130 to automatically detect the oil/water transition andtotalize the oil production from the sensor data. The oil productiondata is then fed to the remote station where an advanced algorithmand/or artificial intelligence system gathers the production data andadjusts the output of the oil recovery system and tool automatically tooptimize oil field performance autonomously.

As another alternative, some or all of the components depicted in FIG.25 , including the optional motorized reel 1300 for raising and loweringthe flexible conduit, may be trailer-mounted to make the system 1210more portable. And, in implementing a trailerable embodiment, it mayalso be possible to include alternative, uniform and/or backup powersystems so that down-time due to interruptions in power to the systemlocation can be reduced or eliminated.

Referring to FIG. 28 , depicted therein is a schematic illustration ofan oil recovery tool 110. As has been described above in variousembodiments, and as generally represented by the components in thefigure, the oil recovery tool comprises three principal components: avalve 2130, a motor 2120, and an accumulator 2180. The submersible oilrecovery tool 110 is employed to impart seismic wave energy within anoil reservoir to alter the capillary forces of the residual oil andmobilize it to improve oil recovery from the reservoir, for example asillustrated in FIGS. 25-26 .

As a functional summary of the various embodiments disclosed herein, onepurpose of the valve 2130 is to generate the seismic waves that arepropagated through the reservoir. A purpose of the motor 2120, which ismechanically coupled to the valve and provides a mechanical force tomove or actuate the valve, is to open and close the valve in response tosignals received by the motor. In one embodiment, it is contemplatedthat the motor, in response to such signals, operates the valve in aperiodic manner. For example, the valve may be operated by the motor togenerate waves within a frequency range of about 10 Hz to about 100 Hz,and more particularly a frequency range of about 15 Hz to about 50 Hz.It will be appreciated, as described above, that the frequency and othercharacteristics of the seismic waves is, at least to some extent,subject to customization and optimization for the conditions in whichthe oil recovery tool 110 is deployed. The nature of the valve 2130 isnot specifically defined in the schematic and is intended to incorporatelinear, rotary (rotor and stator) or other types of valves. Thesimilarity of the valves is that two components, each having a port oraperture therein are moved relative to one another so that the portscontrollably, and possibly with regular periodicity or frequency, alignwith one another to allow pressurized fluid to escape and generate theseismic wave.

The purpose of the accumulator 2180 is to refine and intensify theseismic pulse generated by the oil recovery tool. When the valve 2130 isclosed, pressure briefly increases and fluid flows into the accumulator,compressing a compliant chamber (e.g., formed with a spring-loadedpiston or a pre-pressurized (nitrogen-filled) bladder). When the valve2130 opens, pressure is released, forcing the fluid out of theaccumulator. The necessary fluid flow includes a combination of pressureand volume/time (flow rate) of the fluid. And, the necessary fluid flowis to at least some extent dependent upon the type of fluid employed aswell as the desired seismic wave characteristics.

In one embodiment, motor 2120 may include a speed ratio mechanism (e.g.,gear train, transmission, etc.) capable of increasing or reducing theoutput rpm from the motor to the input rpm to the rotary valve tooptimize the operation of the valve to maximize the potential of thetool to improve recovery. The motor 2120 may be either electrically orhydraulically powered. Either means of powering the motor may beemployed depending on the operating conditions present where the tool isdeployed. Electric motors have the advantage of being able to vary thevalve's pulse rate independent of injection rate while the tool isdeployed. Hydraulic motors, which may include a progressive cavity pump,have the advantage of not requiring an electric power cable attached tothe tool and run back to the surface.

It should be understood that various changes and modifications to theembodiments described herein will be apparent to those skilled in theart. Such changes and modifications can be made without departing fromthe spirit and scope of the present disclosure and without diminishingits intended advantages. It is therefore anticipated that all suchchanges and modifications be covered by the instant application.

What is claimed is:
 1. An oil recovery system for enhancing the recoveryof oil within a reservoir, including: a source of pressurized fluid; asubmersible oil recovery tool for imparting seismic wave energy withinthe oil reservoir, in the form of a wave, to alter the capillary forcesof residual oil therein, comprising, a housing; and a frameless,fluid-saturated motor, operatively located within said housing to drivea rotary valve including a rotor having at least one port rotatingrelative to at least one port in the housing, an accumulator, fluidlyconnected to the rotor to receive the pressurized fluid and generate theseismic waves by release of the pressurized fluid upon alignment of theat least one rotor port with the at least one port in the housing, saidmotor permitting the flow of the pressurized fluid from the source ofpressurized fluid, through the motor to the rotor and the fluidlyconnected accumulator; and a control system suitable for monitoring andcontrolling the system components including at least the oil recoverytool and the source of pressurized fluid to produce the seismic waveswithin the reservoir.
 2. The oil recovery system according to claim 1,wherein said source of pressurized fluid includes: a source ofreplenishable liquid; a pressurization system for pressurizing theliquid from said source of replenishable liquid and passing thepressurized liquid through a conduit to the oil recovery tool.
 3. Theoil recovery system according to claim 2, wherein said pressurizationsystem includes a pump in combination with a filter, along with at leastone sensor generating a signal and sending said signal to said controlsystem.
 4. The oil recovery system according to claim 2, wherein saidconduit is capable of handling a fluid pressure of up to at least 7500psi.
 5. The oil recovery system according to claim 1 wherein saidsubmersible oil recovery tool further comprises, an accumulator, and anacoustic wave generator operatively connected to said fluid-saturatedmotor.
 6. The oil recovery system according to claim 5, wherein saidacoustic wave generator includes a rotary valve with a rotor and stator,each having ports therein, said rotor being operatively connected tosaid fluid-saturated motor.
 7. The oil recovery system according toclaim 6 wherein said accumulator is positioned below the rotary valvewhen the submersible oil recovery tool is in the reservoir.
 8. The oilrecovery system according to claim 6 wherein said accumulator ispositioned above the rotary valve when the submersible oil recovery toolis in the reservoir.
 9. The oil recovery system according to claim 6wherein the accumulator is positioned above the rotary valve and themotor is positioned below the rotary valve when the submersible oilrecovery tool is in the reservoir.
 10. The oil recovery system accordingto claim 5, wherein said accumulator includes a compliant chamber. 11.The oil recovery system according to claim 1, wherein said rotary valvefurther includes at least one hydraulic bearing employing thepressurized fluid to reduce friction.
 12. The oil recovery systemaccording to claim 11, wherein said rotor includes a plurality of smallports permitting the flow of the pressurized fluid to the at least onehydraulic bearing.
 13. An oil recovery tool for imparting seismic waveenergy within an oil reservoir, in the form of a wave, so as to alterthe capillary forces of residual oil comprising: a source of pressurizedfluid; and a housing including an accumulator in fluid connection with aframeless, water-saturated motor within the housing to drive a rotatingvalve having a rotor with at least one port rotating relative to atleast one port in the housing, an accumulator, fluidly connected to therotor to receive the pressurized fluid and rotate the rotor to generatethe seismic waves by release of the pressurized fluid in the accumulatorupon alignment of the at least one port of the rotor with at least oneport in the housing.
 14. An oil recovery system for enhancing therecovery of oil within a reservoir, including: a source of pressurizedliquid; a submersible oil recovery tool for imparting seismic waveenergy within the oil reservoir, in the form of a wave, to alter thecapillary forces of residual oil therein, comprising, a housing; and anacoustic wave generator, operatively located within said housing toreceive the pressurized liquid and generate the seismic waves throughcontrolled release of the pressurized liquid; and a control systemsuitable for monitoring and controlling the system components includingat least the oil recovery tool and the source of pressurized liquid toproduce seismic waves within the reservoir, wherein said control systemincludes: a programmable logic controller; a single-board computer; andat least one external communication transceiver, wherein theprogrammable logic controller provides low-level controls by interfacingwith and providing control signals and power to the acoustic wavegenerator in the oil recovery tool, and where the single-board computeris operatively connected to exchange commands and data with theprogrammable logic controller to effectuate various operations of theoil recovery system to consistently produce the seismic waves.
 15. Theoil recovery system according to claim 14, wherein said acoustic wavegenerator further includes a frameless, water-saturated motor,operatively located within said housing and connected to a rotoroperatively associated with a stator to receive the pressurized fluidand generate the seismic waves by release of the pressurized fluid. 16.The oil recovery system according to claim 15, wherein said motorpermits the flow of the pressurized fluid therethrough.
 17. The oilrecovery system according to claim 15 wherein said submersible oilrecovery tool further comprises, an accumulator, and an acoustic wavegenerator operatively connected to said water-saturated motor.
 18. Theoil recovery system according to claim 17, wherein said acoustic wavegenerator includes a rotary valve with a rotor and stator, each havingports therein, said rotor being operatively connected to saidfluid-saturated motor.
 19. The oil recovery system according to claim 18wherein said accumulator is positioned below the rotary valve when thesubmersible oil recovery tool is in the reservoir.
 20. The oil recoverysystem according to claim 17, wherein said accumulator includes acompliant chamber.